Monthly Archives: February 2018

Amateur Radio, Classes, Makerspaces

Learning with Hams…

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Students learn about Amateur Radio Technician license privileges.
Students learn about Amateur Radio Technician license radio privileges and operating procedures.

Last night PCAUXCOM, the local Amateur Radio emergency communications group, began a FCC Amateur Radio operator’s license class at Castlemakers. It’s a great way to study for the test – although you can self-learn the material to get a license.

What they’re doing however embodies what often happens with vocations and hobbies – people practicing and learning with other people. Not only to learn quicker, but for enjoyment too. It can help make challenging things easier; in some cases even provide focus and accountability. In today’s noisy world with more opportunities than time that’s often difficult.

Makerspaces, and one of Castlemakers’ goals in particular, can bring communities of people together to share knowledge and skills by providing a space, events, equipment, and even just a reason for people to share something. Whether it be a CoderDojo (bringing kids and programmers together to explore programing languages), folks interested in 3D Printing (which also met last night to see printers in use at a high school classroom), or Amateur Radio operators and emergency volunteers assisting others to get a communications equipment operating license.

The PCAUXCOM class is meeting every Monday evenings from 6:30 to 8 pm at Castlemakers, it’s free and open to all, and still not too late to join in. They will also be offering a licensing test locally here in Greencastle just after the course is finished, contact George Edenfield for more information.

Castlemakers Kids

Stealing Joules

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The instructions & a few of the 'thiefs' we made to test out the circuit.
The instructions & a few of the ‘thiefs’ we made to test out the circuit.

This last Sunday, for our first Castlemakers Kids meeting of the year, eight kids (and a few adults) learned about the electronic circuit called the “Joule Thief.” It’s a fun circuit that has gained some popularity in hacker circles, yet a lot of people don’t know about. Two factors make it a good kids project: The simplicity of the circuit and you don’t need to understand the electronics behind it. For inquiring minds it can challenging because it’s not immediately obvious how it works.

A group of the girls at the meeting assemble the parts mostly scavenged from other electronics.
A group of the girls at the meeting assemble the parts mostly scavenged from other electronics.

The name is based on getting extra energy (joules) out of dead batteries. Or at least batteries that most people think are dead. The circuit, with only 4 components, can use as little as .5 volts from a single dead cell AA battery and boost it up over 3 volts – more than enough to light up a white or blue LED. Even a brand new 1.5 volt AA battery won’t do that! For the more technically minded it’s a simple blocking oscillator (IMHO not an Armstrong since there’s no capacitor) that pulses higher voltage using a inductor, resistor, and a transistor.

There are lots of different ways to make the circuit, which turned out to be part of the fun. We tore apart computer power supplies to get the toroid coils, but also experimented using parts from burned out Compact Fluorescent Light (CFL) bulbs too. We found out the CFL parts worked great & possibly how we’ll do it in the future – although it can be tough to wind the toroid from some of the newer CFL bulbs. One future experiment – the Joule Thief circuit can charge dead rechargeable batteries, another great way to get energy out of supposedly dead batteries!